Olympic security and rescue boats are adhesive bonded for rigidity  31 Jan 2012

Ribcraft designs and manufactures 150 custom rigid inflatable boats a year

Resin mixing equipment played a key role in the on time delivery of rescue boats designed for use in this year’s Olympic sailing regatta in Portland and Weymouth.

Ribcraft security rescue boats will be used in all the outdoor water sport events at the 2012 games

Early Olympic success goes to Ribcraft, a company based in Yeovil which has successfully delivered 64 security rescue boats which will be used in all the outdoor water sport events at the 2012 Olympic Games.

To comply with this tight schedule a different production method was required, which needed to consider available factory space and labour because normal production had to continue to satisfy existing customers. The conventional hand layup method would have taken up too much space in their factory so anew concept was created, which meant three pre-formed layers being brought together and bonded. This would enable batch building 10 boats at a time, the problem now was how to bond them together without any mechanical fixing.

After extensive trials, Crestabond M1-30 10:1 ratio structural adhesive from Scott Bader was chosen due to its high tensile strength and speed of use in this difficult and challenging application. Due to the volume of adhesive being used, Ribcraft chose to use Liquid Control bulk dispensing equipment to ensure accuratedispensing and mixing of both parts to maximise bonding performance.

Early Olympic success goes to Ribcraft, a company based in Yeovil which has successfully delivered 64 security rescue boats which will be used in all the outdoor water sport events at the 2012 Olympic Games.

Liquid Control has specialised in resin mixing equipment for 40 years and had the expertise and experience to supply equipment suitable for this task. Ribcraft founder Mark Gardiner commented: “For the Olympic boats we used a different manufacturing process which meant we had to structurally bond together three pre-formed sections and it was vital that the mixed adhesive performed extremely well because that’s all that is holdingthem together. I realised early on that the adhesive is only as good as the quality of mixing and Liquid Control gave us the precision and technical support we needed and with the added benefit that we were able to save money by reducing resin wastage because of the accuracy of the Liquid Control equipment, which also enabled us to control the adhesive placement precisely ensuring optimum adhesive strength.”

Bulk dispensing equipment ensures accurate mixing of both parts of the adhesive to maximise bonding performance

Gardiner has long had a passion for subsea diving and in 1991 he decided todesign and manufacture his own boat that would be better suited for his hobby as there was nothing on the market at the right price and specification for his diving needs. This was the beginning of what is now a dynamic company employing 38 people, designing and manufacturing 150 custom rigid inflatable boats a year, with an annual global turnover of £4million.

Ribcraft’s sales market has been the hobby and leisure sector. However, this has changed over the last few years with the main expansion being in the professional areas of marine security, involving police and private contract companies who patrol against terrorist, drug and people trafficking. And so it was against this background that Ribcraft received the tender to quote, one of twenty nine that was sent out worldwide from the Olympic governing body, to manufacture 64 safety rescue boats for the 2012 Games. This process started in 2009 and concluded with Ribcraft being awarded the contract in 2010 worth £800,000. Work started on the boats in November 2010 and finished on time in June 2011.

LIQUID CONTROL 01933 277571.

The manufacturing technique enables batch building of 10 boats at a time

Methacrylate structural adhesive

Crestabond M1-30 is a toughened, two component acrylic adhesive designed for bonding composites, thermoplastics and metals. This new generation of structural methacrylate adhesive meets the bonding requirements of most assembly operations, demonstrating good impact, peel, shear, compressive strength and fatigue resistance properties across all bonded parts. The adhesive is a primerless adhesive, requiring only minimal surface cleaning of the substrates to be bonded and demonstrates high toughness in all assembled parts with a gap filling capability up to 50mm.The material is supplied ready to use in pre-packed 400ml co-axial cartridges and in bulk (20 litre pails and 200 litre drums). Prior to bonding, ensure the substrate surface is clean by following instructions provided. Bulk dispensing equipment should be in good operating condition. Dispense the adhesive at slow rate initially onto a non-bonding surface until the bead colour is a uniform opaque grey. Check the dispensed bead for cure quality before beginning the bonding assembly. Dispense enough adhesive to fill the bond gap before parts are mated. Avoid dry bond by using adequate pressure to mate parts, and clamp properly to prevent joint movement.All these processes must be completed before the working time of the mixed adhesive expires. To ensure thorough cure, the adhesive must be applied at temperatures between 18°C and 26°C. The effect of temperature upon this working time can be seen in the graph above. The viscosities of both adhesive and activator are affected by temperature. To ensure consistent dispensing in meter-mix equipment, adhesive and activator temperatures should be held reasonably constant throughout the year.

SCOTT BADER 01933 663100

Posted in News from Liquid Control Limited on 31 Jan 2012.